Washington  - The United States on Tuesday slapped import duties on Canadian lumber, the latest twist in a long-running trade dispute between the two neighbours.

US trade representative Ron Kirk said that the US would impose a 10-per-cent customs duty on one of Canada's key exports until the United States has collected 54.8 million dollars it is owed under the terms of a 2006 trade deal.

The United States claims that Canada improperly calculated export taxes for lumber from four of its provinces at the start of 2007. An arbitration court in London sided with the United States in February, ruling that Canada owed 54.8 million dollars.

A Canadian offer of 36.66 million dollars to settle the dispute was rejected last month by the US.

"We regret that Canada has chosen not to meet its commitments and has made this action necessary," Kirk said in a statement.